Conditional rules and variables

How to branch the flow with rules, comparators, and variables

Conditional rules decide the flow’s path: they compare a value (an answer or a variable) and, if the condition holds, route to the next node or to an action.

Comparators by type

Not every comparator applies to every type. The always comparator is the default branch and applies to any type.

Type	Comparators
Text	equals, not_equals, contains, starts_with, ends_with, any_of
Numeric	equals, not_equals, greater_than, less_than, greater_or_equal, less_or_equal, between
Date	equals, not_equals, before, after, between
Boolean	equals, not_equals
Multiple choice	equals, not_equals, any_of

between takes a pair of values (two numbers or two dates); any_of takes a list.

Literal value or variable

The right-hand side of a rule can be a literal value or another variable (variable-to-variable comparison). Both sides must resolve to the same type. Variable comparison is allowed for: equals, not_equals, contains, starts_with, ends_with, and the ordering comparators (greater_than, less_than, before, after, etc.); not for between, any_of, or always. Multiple choice cannot be compared against a variable.

Variables

Built-in variables:

Variable	Type
patient.first_name, patient.last_name	text
protocol.title, protocol.description	text
run.sequence_number, run.previous_score	number
date.today, date.next_call	date
date.now_hour	number (0–23, in the session’s timezone)
question.<key>.answer	depends on the question
webhook.<key>.success / .http_status / .result…	boolean / number / webhook data

Custom variables: declared per version (lowercase name, type text/number/date/boolean, required or not, with an optional default) and referenced as custom.<name> or {{ name }} in templates. Their values come from the enrollment or the run.

Where rules can live

• On a question or a webhook, a rule may only read that node’s own value.
• Any condition that crosses items (another question, a variable, another webhook, or variable-to-variable comparison) must live on a decision node.
• A flow phrase allows at most one rule, and it must be always.